The section continues to investigate pharmacological and behavioral treatments of substance abuse and interactions between these two forms of treatments. A primary objective of these studies is to eliminate drug use and decrease the probability of HIV transmission in cocaine- and/or heroin-dependent patients. Abstinence reinforcement, a behavioral treatment approach in which patients receive incentives for drug abstinence, and methadone maintenance are both effective treatments for drug abuse. We have conducted a study evaluating abstinence reinforcement, methadone dose increase, and their combination compared to standard treatment without dose increase. Patients who continued to use opiates during the first 5 weeks of methadone maintenance (50 mg/day PO) were randomly assigned to one of 4 experimental groups: contingent vouchers for opiate-negative urine specimens plus a 20 mg methadone dose increase; contingent vouchers plus no methadone dose increase; 20 mg methadone dose increase plus noncontingent vouchers; and noncontingent vouchers plus no dose increase control group. Opiate use decreased during the intervention period in all three groups receiving either contingent vouchers or dose increase or both group, but not in the control group. However, only those groups receiving contingent vouchers had significantly increased periods of sustained abstinence. Thus, abstinence reinforcement and methadone dose increase were equally effective in decreasing opioid use, and abstinence reinforcement selectively increased sustained abstinence. However, combined dose increase and abstinence reinforcement was not more effective than either treatment alone. Earlier research in our laboratory showed that abstinence reinforcement contingencies are effective in producing significant periods of cocaine abstinence in inner-city, intravenous, polydrug abusers. The effects of this treatment, however, tend to be short lived in many patients. A cognitive/behavioral relapse prevention counseling approach to substance abuse treatment developed in our laboratory is being integrated into the behavioral contingency management program to increase the duration of abstinence produced by the behavioral treatment alone by encouraging long-term changes in drug use and other HIV risk behaviors. A study evaluating the combination of abstinence reinforcement and relapse prevention counseling is underway.